President Barack Obama on Tuesday requested $3.7 billion in emergency funding from Congress to help cope with a surge of unaccompanied child immigrants from Central America.

Obama said the funds, far higher than the president signalled he would request late last month, would help ease an “urgent humanitarian situation” that has seen tens of thousands of minors from El Salvador, Guatemala and Honduras illegally cross the southern US border this year.

To stem the flow, the administration seeks to beef up border security with aerial surveillance, improve housing for the undocumented arrivals and speed up their deportations.

The appropriation would go to several US government agencies and fund an increase in immigration judges, asylum officers and border agents, expand court capacity, and add detention facilities, the officials said.

A main goal is to speed up turnaround times for deportations, with one White House official saying “we are prioritizing recent border crossers.”

Obama, in a letter to House Speaker John Boehner, urged Congress to “act expeditiously.” He said the funds, in addition to strengthening border security, would help cover “the operational costs of responding to the significant rise in apprehensions of unaccompanied children and adults travelling with children, and expenses associated with the appropriate care for those apprehended.”

The funds would also expand the government’s Alternatives to Detention program through increased use of ankle bracelets that would allow migrants to stay with relatives instead of in over-crowded, expensive detention facilities while their cases are being processed.

“We are taking an aggressive approach on both sides of the border,” a White House official told reporters, referring to US efforts to coordinate with Mexican and Central American authorities to prevent migrants from taking the perilous journey to the United States, often with dangerous human traffickers.

“We are taking steps to both protect due process but also to remove these migrants efficiently,” said the official, who spoke on condition of anonymity.

A first congressional hearing on the emergency request will occur Thursday before the Senate Appropriations Committee, where Department of Homeland Security (DHS) Secretary Jeh Johnson is scheduled to testify.

Johnson was in Guatemala Tuesday to discuss efforts to reduce illegal immigration.

Obama travels to Texas on Tuesday. He will not visit the border region, but he has invited Governor Rick Perry to meet with him in Dallas to discuss the immigration crisis.

Under the plan, DHS will receive $1.5 billion, including $116 million to pay for transporting migrants back to their home countries.

The Department of Health and Human Services will be allocated $1.8 billion, mostly to provide care for unaccompanied child migrants.

The State Department will receive $300 million to repatriate Central American migrants, address the underlying causes driving migration, and launch media campaigns emphasizing that illegal immigrants will not be allowed to stay in the United States.

The plan is not a done deal, especially in a divided Congress. But the White House officials said they were confident that the emergency request would be taken up in a “spirit of bipartisanship.”

Boehner’s office said the border crisis working group he appointed will review the proposal.

“The speaker still supports deploying the National Guard to provide humanitarian support in the affected areas — which this proposal does not address,” a Boehner spokesman said.

The hefty cost may be a sticking point, especially for Republicans loath to approve major spending projects in an election year.

Immigration has exploded into a flashpoint issue. Protesters in a small California town, home to a US Border Patrol facility for detained migrants, last week blocked three buses transporting migrant women and children.

According to the White House, Immigration and Customs Enforcement has deported some 233,000 people in fiscal year 2014, including 87,000 from Central American countries.

Since last October, more than 52,000 unaccompanied child migrants, two thirds of them from Central America have crossed illegally into the United States, US officials said.